GeForce 9800 GT 1GB vs Radeon HD 4850 512MB

Intro

The GeForce 9800 GT 1GB makes use of a 65/55 nm design. nVidia has clocked the core frequency at 600 MHz. The GDDR3 memory runs at a frequency of 900 MHz on this particular model. It features 112 SPUs as well as 56 Texture Address Units and 16 Rasterization Operator Units.

Compare all that to the Radeon HD 4850 512MB, which uses a 55 nm design. AMD has set the core frequency at 625 MHz. The GDDR3 RAM is set to run at a speed of 993 MHz on this model. It features 800(160x5) SPUs as well as 40 TAUs and 16 Rasterization Operator Units.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the maximum amount of data (measured in MB per second) that can be transported past the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly record to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.